"We're here to let the military know what they did is wrong, the coup was illegal," Nongnuch Karunyalert, 47, told Al Jazeera. She wore a black shirt on top of a red one, saying it was too dangerous now to wear the colour that represents the political followers of ousted prime ministers Thaksin and Yingluck Shinawatra.

"I was warned this week not to wear red any more, as the soldiers are targeting those who do. Four years ago these soldiers killed about 90 of our people. These guys are dangerous," Nongnuch said, referring to the 2010 crackdown on Red Shirts who had occupied Lumpini Park in central Bangkok for months after another of their governments was removed from power.

A motorcycle taxi driver, who asked to be identified only as Boy, said anger was growing among supporters of the latest government to fall. "We have to boycott what the army has done here," he said. "They need to set up a government quickly."

Independent analyst Benjamin Zawacki told Al Jazeera he was not surprised that the pro-government side had taken to the streets, adding it likely had prepared a response even before martial law was declared last Tuesday. "I am actually surprised there weren't more pre-emptive protests beforehand," he said.

More than 1,000 protesters also converged on Democracy Monument on Sunday, many walking many kilometres from the McDonald's demonstration site and collecting others along the way.

"I think the army coup is against democracy and people want an election in a modern democratic Thailand," said Sirawith Seritinat, 22, a student at Thammasat University in Bangkok. "I agree with some ideas from the Red Shirts, but I do not support them. However, we need a government elected by the people, and not appointed."

Elections?

It remains unclear when, or if, the military plans to install a new government and call elections. Thaksin and his allies have won every poll since 2000, and based on the current political system would likely do so again because of vast voter support in the country's populous north and northeast.

Opponents of the Red Shirts and their politicians, mostly the urban middle class and elite based in Bangkok, have demanded that the political system be reformed before any new election is called.

"We seek for a kind understanding of the situation in our country. One template cannot be applied to every situation," army deputy spokesman Werachon Sukhonpatipak told Al Jazeera.

General Prayuth Chan-ocha, the army chief who now fully controls the country, has ordered politicians, scholars and journalists to present themselves at military offices.

On Saturday, the general dissolved the Senate, the last functioning body of government left standing to run the country.

"I'm surpised he [Prayuth] dissolved the Senate," said Zawacki, who is writing a book on southeast Asian politics. "I would not have thought he'd want to have to deal with the technocratic side of running the country. He had a ready-made body of qualified, diverse people to keep the government going. Now he has taken on all that power for himself."

Zawacki said that after the 2006 coup that ousted Yingluck's brother Thaksin, the army proved "less than fully capable of running the government".

Patitan Prueksakasemsuk, 22, is the son of Thai activist Somyot Prueksakasemsuk, who was jailed under Thailand's harsh lese-majeste law for insulting the monarchy. Back at Democracy Monument, Patitan said he joined other student protesters to let the army know that the status quo cannot prevail.

"I'm against what has happened because I think the citizens have the right to vote. I know I could be arrested, but I am ready for this," he told Al Jazeera.

Reforming democracy

The burning question now is what the military intends to do with the power it has seized. Zawacki noted that there has been little talk about restoring civilian rule since the coup unfolded.

"The signs are not good given the fact that there's been no mention of democracy, an election and a timeframe for that," Zawacki said.

"Any semblance of government has been dissolved. And if you read the tea leaves, it does look like this [military rule] could be indefinite. There's been no indication yet of restoring civilian rule."

Opponents of the Shinawatras and other Red Shirt politicians began demonstrations in November that paralysed the country for months and led to sporadic violence that killed about 28 people.

Prime Minister Yingluck dissolved parliament and called elections in February which her Pheu Thai Party easily won, since the main opposition Democrat Party boycotted the vote.

The Election Commission, which ousted Yingluck earlier this month in a ruling over nepotism, then nullified the vote.

The Red Shirts are pushing for a new election, but their opponents say an overhaul of the political system must first take place, accusing the Shinawatras of buying the votes of the mostly rural poor in the northern provinces with populist policies such as cheap healthcare and rice subsidies.

A 56-year-old librarian, who asked to remain anonymous because she was afraid of reprisals, said she doesn't like the word "coup" because the army's move was made "to have peace in the country".

"It was necessary for the army to take power because Thaksin and his family are corrupt. Thaksin bought a lot of votes," she told Al Jazeera. "I am happy with the army takeover because I trust them more than Yingluck, and maybe with them we'll have more stability."